Doorknobs



K. HOLSCHER DOORKNOBS Filed March 27, 1967 Krun Housnura duuu k 6tlorneys United States Patent 01 iice 3,532,374 Patented Oct. 6, 19703,532,374 DOORKNOBS Knud Holschcr, Horsholm, Denmark, assignor to G. &S. Allgood Limited, London, England, a British company Filed Mar. 27,1967, Ser. No. 626.073

Claims priority, application Great Britain, Mar. 29, 1966,

Int. Cl. Eb 1/00, 3/00 US. Cl. 292-336.?) Claims ABSTRACT OF THEDISCLOSURE This invention relates to a doorknob, intended to be graspedfor the opening or closing of a door. Such knob may be fixedly securedto the door or alternatively may be rotationally mounted thereon for theactuation of a catch member for latching the door in its closedposition. Hitherto, such a doorknob has usually had a narrow neck orstem with an enlarged head shaped for convenient grasping by the wholehand.

The present invention has for its object to provide an improved shape ofdoorknob, which, whilst having advantages for normal users, isespecially advantageous for use by persons having injured or crippledhands, for whom the grasping of an ordinary doorknob presentsdifficulty.

The doorknob, according to the invention, is of cylindrical shape,except that it has a groove cut away on one side for the reception of afinger. The generators of the surface of the groove preferably all lieat right angles to to the direction of the axis of the cylinder. Thefront face of the doorknob is preferably plane and at right angles tothe axis of the cylinder.

Such a doorknob may be fixedly secured to the door, with its rearsurface in contact either with the door surface or with the surface of aplate secured to the door.

Alternatively, the doorknob may be rotatably mounted on the door andsecured to a shaft which actuates a catch member serving to latch thedoor in its closed position. Conveniently, the doorknob is detachablysecured to a squared actuating shaft, for example by means of a grubscrew, so that it can be secured thereto in any one of four positionsgiving different orientations of the groove in the knob. It isespecially advantageous, when the doorknob is made of metal, to employ awasher of plastics material, in the form of a hollow cylinder with anexternally projecting flange at one end, such washer being interposedbetween the doorknob and a metal member secured to the door, for thejournalling both axially and radially of the knob in such member. Thus,the flange of the plastics washer may be interposed between the rearsurface of the doorknob and the surface of a metal plate secured to thedoor, whilst the cylinder of such washer is interposed between the outersurface of a cylindrical projection on the knob and the cylindricalsurface of a circular hole in such plate.

The invention may be carried into practice in various ways, but someconvenient alternative practical constructions of doorknob accordingthereto are illustrated by way of example in the accompanying drawings,in which:

FIGS. 1 and 2" show one construction of fixed doorknob respectively inplan and in front elevation,

FIGS. 3 and 4 show a second construction of fixed doorknob alsorespectively in plan and in front elevation,

FIG. 5 shows a construction of rotatable doorknob in plan, and

FIG. 6 illustrates the door latching mechanism actuated by the rotatabledoorknob of FIG. 5.

In all these arrangements, the main body of the knob consists of acylindrical metal block, with parallel flat ends at right angles to theaxis of the block, having a groove cut away on one side. Such groove hasa smoothly curved surface, with its generators parallel to the fiat endsof the block, the dimensions of the groove being such as comfortably toreceive a finger. Thus, in practice, the knob is grasped, not by thewhole hand as in previously known doorknobs, but between the side of theforefinger in the groove and the thumb lightly pressed against theopposite side of the knob.

The various arrangements now to be described differ from one anothermainly in the manner in which the main body of the knob, asabove-described is mounted on the door. In some instances, the knob isfixedly secured to the door, as is often required for example forcupboard doors, whilst in other instances the knob is rotatably mountedfor the operation of a catch member for latching the door in its closedposition, as is usual for room doors. Usually, it will be preferred toemploy a smaller size of knob, when the knob is fixedly secured to, say,a cupboard door, than when the knob is rotationally mounted for use forexample on a room door. Since both sizes of knob are intended to begrasped by inserting a finger in the groove, the groove in the smallersize knob cannot be very much smaller than that in the larger size knobalthough there may be a large difference between the sizes of the knobitself. Thus, the relative proportions will be different in the twosizes of knob, and the small size knob will not be a true scalereduction of the larger size knob.

FIGS. 1 and 2 show a simple arrangement in which the knob is intended tobe fixedly secured to the door, for example a cupboard door. For thispurpose, the generally cylindrical main body A of the knob, with itsfinger groove A on one side, has tapered and pointed screwthreaded shankB formed integrally with it or rigidly secured to it, such shankprojecting from the rear flat face A of the main body of the knob. Theknob can thus be screwed directly into the door itself and, when soscrewed in, the rear face of the knob will be in firm contact with thedoor surface.

In the arrangement of FIGS. 3 and 4, the knob, having a cylindrical mainbody C with finger groove C on one side and with flat rear and frontfaces C and C is again fixedly secured to the door D, but in this case asurface metal plate E is interposed between the knob and the doorsurface. In this arrangement it is preferred, first to secure the knobto the plate E, and then to secure the plate to the door surface. Forthis purpose, the rear face C of the knob is bored with one or morescrewthreaded holes, and a registering hole or holes are cut through theplate, so that the plate and the knob can be secured together in closecontact by inserting a screw E or screws through the plate E into thescrewthreaded hole or holes in the knob C, the screw or each screwpreferably having its head counter-sunk into the plate. The plate E isthen secured to the door by means of screws E passing throughcounter-sunk holes E in the plate.

In both the above arrangements care should be taken to orient the grooveA or C in the desired position when secured to the door. Thus, if theknob is at normal level in front of the head or the upper part of thebody of a normal sized person, the best orientation of the groove willbe on one side of the knob, usually the right-hand side, so that it canbe comfortably grasped between the forefinger and the thumb of the righthand. If, however, the knob is at a higher level, it will be moreconvenient for the groove to lie across the top of the knob, so that afinger can be hooked into the groove for opening or closing the door.Similarly for a low-level knob, the best orientation for the groove willbe across the bottom of the knob.

In the third arrangement shown in FIGS. and 6, the knob F is rotatablymounted for the operation of a catch member G housed in a lock casing Hof the mortice type, such lock casing being secured in an opening cutfrom the edge of the door I between the two door surfaces. In thisarrangement, there will usually be two door knobs F, one on each side ofthe door, and each with a side groove F and with parallel plane rear andfront surfaces F F with a plate K secured to each door surface betweenthe knob F and the door J.

The catch member G is mounted in the lock casing H so as to be movablelongitudinally therein and is urged outwardly by a spring L so that itnormally projects from the edge of the door into engagement in a recesscut in the door frame, such recess being covered by a metal plate M cutwith a hole to receive the catch member. The projecting portion G of thecatch member G has its front surface parallel to the door surfaces andits rear surface at an angle thereto, for example 45 degrees, so thatwhen the door is being closed from an open position, the oblique face ofthe catch member will engage with the fixed metal plate M on the doorframe, which will push the catch member inwardly in the lock casing Hagainst the action of the spring L, until the front surface of the catchmember passes the edge of the hole in the fixed metal plate M, whereuponthe catch member will spring outwardly into the recess and will latchthe door in the closed position.

Within the lock casing, the catch member G has two projecting pins G Gwith one of which G one arm N of a crank lever N N engages. This cranklever is pivoted at N to the lock casing H, and its other arm N isengaged by the spring L.

The crank lever N N is also engaged by one of the arms 0 of a pivotedlever 0 0 the other arm 0 of which engages with the second catch memberpin G At its pivot, the lever 0 0 has a boss 0 with a squared hole,through which passes a squared actuating shaft P, such shaft projectingfrom the lock casing H and passing through. openings cut inwardly fromthe two surfaces of the door I, and also through circular holes in thetwo metal plates K secured to the two door surfaces.

Each door knob F has an integral cylindrical projection F from thecentre of the rear face F of the knob, such projection and also the mainbody of the knob having a squared hole bored in it for the reception ofan end of the squared actuating shaft P. Mounted on such cylindricalprojection F is a washer made of plastics material, for example nylon,consisting of a short hollow cylinder Q with an externally projectingflange Q at one end. The internal surfaces of the cylinder Q of thewasher fits closely around the cylindrical projection F on the door knobF, and the external surface thereof fits closely within the cylindricalsurface of the hole in the metal plate K. The projecting flange Q of thewasher engages on one side with the rear face F of the main body F ofthe door knob and on the other side with the outer surface of the metalplate K.

Each of the two door knobs F is firmly secured to the squared actuatingshaft P by means of a grub screw P engaging in a screwed hole in thedoor knob and pressing firmly against one of the four faces of thesquared actuating shaft. It will be clear that there are thus fourpossible positions of the knob F on the shaft P, and the particular oneof such positions used should be chosen to suit the best orientation ofthe groove in the knob, in accordance with the level at which the knobis located, in the manner above described.

-In operation, with the door I latched in the closed position, theturning of either door knob F in either direction from its normal restposition will cause the catch member G to be withdrawn against thespring action and will thus unlatch the door, the catch member returningto its normal projecting position as soon as the door knob is released.The plastics washers QQ afford much better sliding bearing surfaces withthe metal surfaces, with which they engage, than the metalto-metalbearing surfaces that would otherwise exist if such washers were notprovided, especially if aluminium or an aluminium alloy is used for themetal, as is preferred.

This third arrangement may be modified, if desired by the use of asurface lock casing secured to one of the door surfaces, instead of amortice lock casing. In such case, the door knob on the side of the doorremote from the lock casing will be mounted on a metal plate on the doorsurface, with an intervening plastics washer, in the manner abovedescribed. On the other side of the door, the doorknob will be mountedon the exposed wall of the surface loc-k casing, with an interveningplastics washer, in a manner analogous to that described for themounting of the doorknob on a metal plate.

It will be appreciated that the foregoing arrangements have beendescribed by way of example only and may be modified within the scope ofthe invention in various ways. For example, it is not essential to theinvention that the front surface of the doorknob should be plane and atright angles to the cylinder axis, although from an aesthetic viewpointsuch arrangement is preferred.

What I claim as my invention and desire to secure by Letters Patent is:

1. A doorknob having a cylindrical surface, said surface beinginterrupted on one side only of a diametral plane extending along theaxis of said surface by a groove having a size and position suited toreceive a finger of a hand grasping said knob.

2. A doorknob as claimed in claim 1, in which the front surface of theknob consists of an uninterrupted plane surface at right angles to theaxis of the cylindrical surface.

3. A doorknob as claimed in claim 1, in which the surface of the groovehas parallel straight-line generators lying at right angles to the axisof the cylindrical surface.

4. A doorknob fitting comprising a doorknob as claimed in claim 1, acatch member for latching the door in its closed position, a rotatableshaft for actuating the catch member, and means for securing thedoorknob to such shaft.

5. A doorknob as claimed in claim 3, including means for fixedlysecuring the knob to the door with the rear surface of the knob incontact with a surface carried by the door.

6. A doorknob fitting as claimed in claim 4 in which the knob is made ofmetal, including a metal member secured to the door, and a washer ofplastics material in the form of a hollow cylinder with an externallyprojecting flange at one end, such washer being interposed between theknob and the said metal member and affording bearing surfaces for thejournalling both axially and radially of the knob in the said metalmember.

7. A doorknob fitting as claimed in claim 6 including a cylindricalprojection on the knob, the cylinder of the plastics washer lying inbearing engagement between the outer surface of such cylindricalprojection and the cylindrical surface of a circular hole in a metalplate constituting the said metal member secured to the door, the flangeof the plastics washer lying in bearing engagement between the rearsurface of the knob and the surface of such metal plate.

8. A doorknob fitting as claimed in claim 4, in which the rotatableshaft is of square cross-section, and the securing means permitsdetachment of the knob from such shaft, whereby the knob can be securedto the 5 shaft in any one of four positions giving different orientations of the groove in the knob.

9. A doorknob fitting as claimed in claim 8, in which the knob is madeof metal,including a metal member secured to the door, and a washer ofplastics material in the form of a hollow cylinder with an externallyprojecting flange at one end, such washer being interposed between theknob and the said metal member and affording bearing surfaces for thejournalling both axially and radially of the knob in the said metalmember.

10. A doorknob fitting as claimed in claim 9, including a cylindricalprojection on the knob, the cylinder of the plastics washer lying inbearing engagement between the outer surface of such cylindricalprojection and the cylindrical surface of a circular hole in a metalplate constituting the said metal member secured to the door, the flangeof the plastics washer lying in bearing engagement between the rearsurface of the knob and the surface of such metal plate.

References Cited UNITED STATES PATENTS 745,404 12/1903 Tower 161213,148,406 9/1964 Freiman 16-121 440,187 11/1890 Nehring 292347 1,799,2534/1931 Rogers 292347 2,919,947 l/ 1960 Scott 292-347 3,249,990 5/ 1966Schlage 292347 D. 155,349 9/1949 Lear D503 FOREIGN PATENTS 539,9648/1955 Belgium.

960,771 6/ 1964 Great Britain. 1,084,624 7/ 1954 France.

803,880 4/ 1951 Germany.

RICHARD E. MOORE, Primary Examiner E. J. MCCARTHY, Assistant ExaminerUS. Cl. X.R.

